Method of joining adjacent sheets of elastomeric material on a support structure

ABSTRACT

A method of joining adjacent sheets of elastomeric material to each other and to a support structure. Each sheet includes at least a top and bottom layer of elastomeric material and a layer of reinforcing textile material disposed therebetween and having marginal portions extending beyond said top and bottom layers. The novel method comprises the steps of applying a liquid elastomer solution to the underside of the adjacent marginal portions and pressing the marginal portions against the support structure in an overlapping relation thereby joining said adjacent portions and adhering the joint to the support structure. A liquid elastomer solution is then applied over the joint to provide a continuous outer surface.

United States Patent Inventor Marcel Ecureux Paris, France App]. No. 787,492 Filed Dec. 27, 1968 Patented Nov. 9, 1971 Assignee Strati-France S. A.

Paris, France Priority Jan. 5, 1968 France 135,006

METHOD OE JOINING ADJACENT SHEETS OF ELASTOMERIC MATERIAL ON A SUPPORT STRUCTURE Primary Examiner- Philip Dier Att0rneyAmster & Rothstein ABSTRACT: A method of joining adjacent sheets of elastomeric material to each other and to a support structure. Each sheet includes at least a top and bottom layer of elastomeric material and a layer of reinforcing textile material disposed therebetween and having marginal portions extending beyond said top and bottom layers. The novel method comprises the steps of applying a liquid elastomer solution to the underside of the adjacent marginal portions and pressing the marginal portions against the support structure in an overlapping relation thereby joining said adjacent portions and adhering the joint to the support structure. A liquid elastomer solution is then applied over the joint to provide a continuous outer surface.

This invention relates to methods of fastening and jointing elastomeric sealing or impervious sheets on floors, walls and roofs.

The use of elastomers of different types is widely known for covering terraces and roofs. Generally the sheets are reinforced or supported by various products such as fabric, cardboard, asbestos, expanded or foam plastic, etc.

Regardless of the type or mode of manufacture of these sheets difi'iculty exists in the fastening of these sheets under adequate fluid-tightness conditions both to one another or to a support. Various cements are used to this end, but the covering thus obtained is not uniform in the cemented portions. Alternatively, the sheets may be welded. However, welding, although more satisfactory, is not adequate for making jointless rubberlike coverings.

Accordingly it is an object of this invention to provide a method for fastening adjacent sheets of elastomeric material on a roof or like support structure, with the joint or seam having continuity with the sheets.

In a preferred embodiment of the invention, the sheets consist of a suitable elastomeric material reinforced with a strip of fabric or other relatively loose material of which the marginal ortions project or extend beyond the sheet edges on both sides.

The sheet material is unrolled flat on the support structure, for example a concrete surface. One face of the projecting fabric marginal portion is coated with a layer of liquid elastomer in the form of a solution, emulsion or monomer, so that it will adhere to the underlying support structure. The assembly is allowed to dry or polymerize for the necessary time. When the next width of sheet material is laid the cemented and coated fabric along the marginal portion of the preceding width is covered with the projecting fabric marginal portion of the second width previously coated with a layer of liquid elastomer. Then, the joint thus formed is coated with one or more surface layers for levelling the joint up to the strip.

Thus, the invention provides a novel method for cementing adjacent sheets of elastomeric material in strip fonn to one another and also to an underlying support. At the joint the coating is reinforced by two fabric lips" and the joint is devoid of any lack of continuity that is present when cementing or welding adjacent sheets to one another according to conventional methods.

FIGS. 1 through 3 of the drawing diagrammatically illustrate the steps of the novel method of this invention.

Sheets made from various elastomers such as silicones, neoprene, Hypalon, is a fluorosulfonated polyethylene produced by the US. Company Dupont de Nemours, butyl, isobutylene, etc., polymerizable resins such as polyester, polyether, epoxyresins, etc. can be used for carrying out the method of this invention.

The joint coatings may consist of solutions of these elastomers or liquids prior to their polymerization.

The reinforcing fabric may consist of any suitable material, such as nylon, polypropylene, glass, etc.

If desired, other reinforcing materials may be used in the manufacture of said sheets, such as glass, asbestos, etc.

EXAMPLE I A 3-feet wide sheet is prepared by cementing an asbestos paper sheet (300 grams per sq. m. 0.06 lb. per sq. ft.) to a 0.3 mm. (0.012 inch)-thick rubber sheet of fluorosulfonated polyethylene known as I-Iypalon.

n the surface of this first I-Iypalon sheet there is cemented a glass fabric weighing 52 grams per sq. m. (7 yarns per 0.01

mm.) (i.e. 0.01066 lb./sq. ft.) and then another Hypalon sheet of same thickness (0.3 mm. or 0.012 inch) is cemented thereover.

The sandwich thus obtained is homogeneous throughout its 3-feet width, but the fabric projects from both longitudinal edges of the sheet by about 5 mm. (0.2 inch).

The joint coating may consist for example of:

a solution or emulsion of neoprene rubber in a suitable solvent and containing the additives and fillers usually contemplated for these well-known coatings; this joint coating is applied as a first layer.

' a I-Iypalon rubber solution in a suitable solvent, which is applied as the second layer and as the final layer.

This I-Iypalon coating may contain the desired fillers, pigments, etc. according to the techniques well known in the use of paints of this type.

The sheet thus obtained is unrolled on the roof surface, for example, a concrete surface.

The projecting marginal portions of the fabric are coated by using by using a solution of a product such as neoprene which is allowed to dry during the necessary time, and the next sheet width is then unrolled.

This second width is disposed in such a manner that its projecting fabric covers the previously coated fabric (see FIG. 3).

This projecting portion is cemented by using another layer of rubber or neoprene solution.

The opposition face of the second sheet is coated in turn and receives the projecting fabric portion of the third sheet, and so forth.

The glass fabric may be replaced by a nylon fabric.

EXAMPLE 2 The sheet consists of butyl rubber substituted for the abovementioned Hypalon.

The cementing coating consists of a butyl rubber solution containing adequate vulcanizing agents and fillers. In this case, only one coating is applied to the different sheets.

Referring to FIG. 1, during the first step, the support I to be covered receives a sheet 2 consisting of a suitable elastomer and including therein, a textile reinforcement 3 formed with marginal portions 4 projecting along the longitudinal sides or edges thereof.

During the second step, the lower face of these projecting portions 4 are coated with a joint-forming material 5 such as a liquid elastomer solution (FIG. 2); the edges 4 of the two adjacent sheets are superimposed to each other and the assembly is allowed to dry or polymerize so as to simultaneously assemble or joint the two adjacent sheets and cause them to adhere to the underlying support.

During the third step, a joint is formed along the overlapping marginal portions 4 of the assembled sheets by using a suitable cast product 6 such as an elastomer solution in a suitable solvent, so as to eliminate any discontinuity between these sheets.

What I claim is:

1. A method of joining adjacent sheets of elastomeric material on a support structure each sheet including a top and bottom layer of elastomeric material and a layer of reinforcing textile material disposed therebetween and having marginal portions extending beyond said top and bottom layers, said method comprising the steps of:

a. applying a liquid elastomer solution to underside of the adjacent marginal portions;

b. pressing said marginal portions against the support structure in an overlapping relation thereby joining said adjacent marginal portions and adhering said joint to the support structure;

0. applying a liquid elastomer solution over said joint to provide a continuous outer surface. 

